Solar Panels for Factories in Ireland
Factories and manufacturing sites are among the best buildings in Ireland for solar PV. Large industrial roofs and a high, steady daytime electrical load mean most generation is used on-site, which is where the savings come from. This guide sits under our commercial solar hub and covers sizing, grants and the practical install detail for manufacturing. When you're ready, compare commercial solar quotes from experienced Irish installers.
Last updated November 2026
Fact-checked by John Rooney, Solar Energy Editor. Editorial policy
Quick Answer
Factories in Ireland typically install 50–250+ kWp of rooftop solar, costing roughly €800–€900 per kWp before the SEAI NDMG grant (up to €162,600). Because machinery, compressors and process loads run through the day, self-consumption is high (~80–90%), so a manufacturing system usually pays back in 5–7 years with a 10–15% annual ROI, helped further by 100% ACA tax write-off in year one.
Why factories are ideal for solar PV
A manufacturing site combines two things solar wants: a large, unobstructed roof and a heavy daytime electrical load. Production lines, compressors, extraction, pumps, refrigeration and process heat run during daylight hours, which lines up almost exactly with when solar panels generate. That match is what makes industrial solar so attractive in Ireland, the electricity is used the moment it is produced rather than exported at a lower rate.
Commercial sites with a strong daytime profile routinely reach 80–90% self-consumption. Every unit used on-site offsets imported electricity at roughly €0.22/kWh, while surplus exported under the Clean Export Guarantee earns around €0.18/kWh. Because factories consume so much of what they generate, the return is driven by avoided import cost, not export income.
Large industrial roof
Manufacturing units often have thousands of square metres of flat or shallow-pitched roof, room for 50–250+ kWp with no land take.
Steady daytime load
Machinery, compressors and process heat draw power all day, giving the high self-consumption (~80–90%) that drives payback.
Three-phase supply
Factories already run on three-phase, so larger inverters and arrays connect cleanly without a supply upgrade in most cases.
What size solar system does a factory need?
Most Irish factories install between 50 and 250 kWp, with larger manufacturing and food-processing sites going beyond that. The right size is set by your daytime electricity demand and usable roof area rather than by total annual consumption, you size to soak up the on-site load, not to cover every kWh. As a rule of thumb, 1 kWp needs roughly 4–5 m² of roof and generates about 860 kWh per year in Ireland.
| Factory Profile | Typical System | Roof Area | Annual Generation | Indicative Net Cost |
|---|---|---|---|---|
| Small manufacturing unit | 50 kWp | ~250 m² | ~43,000 kWh | €27,400–€42,400 |
| Mid-size factory | 100 kWp | ~500 m² | ~86,000 kWh | €47,400–€77,400 |
| Large factory / process plant | 200 kWp | ~1,000 m² | ~172,000 kWh | €87,800–€137,800 |
| Major manufacturing / food processing | 250+ kWp | 1,250+ m² | 215,000+ kWh | €112,000–€175,000 |
Net cost is after the SEAI NDMG grant and assumes roughly €800–€900 per kWp installed at commercial scale in 2026. Generation assumes an average Irish yield of 860 kWh/kWp. A site survey of your roof and half-hourly load data will refine the exact figure. Sites with parking can add a solar carport where roof space is limited.
Grants, ACA and payback for factories
Temporary increase: for applications from 7 October 2026 to 6 July 2027 the NDMG is doubled, to a maximum of €325,200. SEAI pays the lower of the doubled per-kWp rate or 45% of the invoiced cost, up from about 23% of the cost of installation. The NDMG figures on this page are the standard rates, so a new application in that window can get up to twice as much. Applications made before 6 October 2026 are not increased. See what the 45% rate means.
Factory solar is funded by the SEAI Non-Domestic Microgeneration Grant (NDMG), not the domestic grant. The NDMG pays a rate per kWp that steps down with size, up to a maximum of €162,600 on larger systems. On top of the grant, trading companies can use the Accelerated Capital Allowance (ACA) to write off 100% of qualifying solar and battery cost against profits in year one, provided the equipment is on the Triple-E register.
| Metric | Typical Factory Range |
|---|---|
| Installed cost | €800–€900 per kWp |
| SEAI NDMG grant | Up to €162,600 (rate per kWp by size) |
| Self-consumption | ~80–90% (high daytime load) |
| Import value offset | ~€0.22/kWh |
| Export rate (CEG) | ~€0.18/kWh on surplus |
| Payback period | 5–7 years |
| Annual ROI | 10–15% |
| ACA tax relief | 100% write-off in year one (Triple-E) |
Why the payback is strong
A factory uses most of its solar on-site, so each kWh displaces grid electricity at the full import rate rather than being sold cheaply. Combine that with the NDMG grant reducing the capital cost and the ACA writing off the balance against profits, and a manufacturing system typically clears payback in 5–7 years while the panels keep working for 25–30. See the commercial solar hub for the full grant table by system size.
Solar panels on Irish manufacturing plants: real examples
Irish manufacturers have been putting solar on factory roofs at scale. The projects below are all published by the company or in the trade and business press. They are much bigger than the typical 50–250 kWp system on an SME factory, but they show what output and share of demand to expect.
| Manufacturing plant | Sector | System | Reported output and impact |
|---|---|---|---|
| Mannok, Co. Cavan | Building products | 6 MW rooftop, ~10,000 panels on 3.88 ha of roof | Work began July 2026; billed as Ireland's largest rooftop array; ~792 t CO₂ avoided a year |
| Carey Glass, Nenagh, Co. Tipperary | Glass manufacturing | 2.7 MW rooftop (2023) | ~2.4 GWh a year; up to 13% of site energy |
| Gyproc, Kingscourt, Co. Cavan | Plasterboard manufacturing | 2.5 MW, 3,556 panels (2026) | ~2,235 MWh a year; up to 15% of site demand; ~€230,000 a year in electricity savings |
| Dawn Meats, Grannagh, Co. Waterford | Meat processing | 3,500 rooftop panels on 8,397 m² (2025) | 1.56 GWh a year; ~40% of site electricity; €1.5m cost, 4.5-year expected payback; no extra planning permission needed |
| Tayto Snacks, Ashbourne, Co. Meath | Food manufacturing | 1,734 rooftop panels (2026) | ~667 MWh a year; about 10% of plant electricity; €1.17m, supported by the SEAI NDMG |
| Irish Cement, Platin Works, Co. Meath | Cement | 1 MW rooftop across two buildings (2026) | Commissioned April 2026 |
Figures as reported by each source (listed at the bottom of this page); generation and savings are the companies' own estimates. Dawn Meats sits at the high end on share of demand because of its large roof relative to load, while Tayto, Carey Glass and Gyproc show the 10–15% typical of energy-intensive plants.
Roof, planning and install considerations
Industrial roofs bring their own detail. Many Irish factory units use trapezoidal metal (profiled steel) roofs, which take non-penetrative or clamped mounting rails fixed to the standing seams or sheet crowns, avoiding holes through the cladding. Older roofs should be checked for remaining lifespan and load capacity before a large array goes up, since panels and ballast add weight.
| Factor | What to check |
|---|---|
| Roof type | Trapezoidal metal vs flat membrane, clamped rails for steel, ballasted frames for flat |
| Roof condition | Remaining lifespan and structural load capacity for the added weight |
| Electrical supply | Three-phase board capacity and inverter sizing to match daytime load |
| Grid connection | ESB Networks NC6 (small) or NC7 (larger, up to 200kW); EN 50549 inverter compliance |
| Planning | Rooftop largely exempt under S.I. 493/2022 within industrial area caps; large arrays may need permission |
Planning and grid connection
Rooftop solar on industrial buildings is largely planning-exempt under S.I. 493/2022 within the area caps that apply to industrial sites, which are more generous than the domestic caps. Very large arrays or any ground-mounted addition can still need permission, so confirm with your installer early. On the grid side, factories connect through the ESB Networks NC6 process for smaller systems or NC7 for larger ones up to 200kW, and inverters must meet EN 50549. These steps run in parallel with the NDMG application, so start them together to avoid delay.
How much could solar save your factory?
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Compare commercial solar quotesFactory Solar FAQ
How many solar panels can a factory roof hold?
It depends on usable roof area. As a rule of thumb, 1 kWp needs about 4–5 m² of roof, so a 1,000 m² roof supports roughly 200 kWp (around 400–500 panels). A site survey accounts for rooflights, plant, walkways and shading before confirming the final layout.
What grant can a factory get for solar in Ireland?
Factories use the SEAI Non-Domestic Microgeneration Grant (NDMG), not the €1,800 domestic grant. The NDMG pays a rate per kWp that steps down with size, up to a maximum of €162,600 on larger systems. Trading companies can also claim 100% Accelerated Capital Allowance against profits in year one.
Why is solar so good for manufacturing sites?
Factories run machinery, compressors and process loads through the day, which matches when solar generates. That gives high self-consumption (around 80–90%), so most electricity is used on-site at the full import rate of about €0.22/kWh rather than exported. That is the main reason payback is typically 5–7 years.
How much of a factory's electricity can solar panels supply?
On large Irish manufacturing plants, published projects report solar covering about 10–15% of annual demand (Tayto about 10%, Carey Glass up to 13%, Gyproc up to 15%), rising to around 40% where the roof is large relative to the load, as at Dawn Meats in Waterford. Because nearly all of it is used on-site, even a modest share pays back quickly.
Can solar panels go on a trapezoidal metal factory roof?
Yes. Profiled steel (trapezoidal) roofs are very common on Irish industrial units and take clamped or non-penetrative mounting rails fixed to the sheet crowns or standing seams, avoiding holes through the cladding. The installer checks the roof's remaining lifespan and load capacity first.
Does a factory need planning permission for rooftop solar?
Rooftop solar on industrial buildings is largely planning-exempt under S.I. 493/2022 within the area caps that apply to industrial sites, which are more generous than domestic limits. Very large arrays or any ground-mounted addition may still require permission, so confirm with your installer.
Related Guides
Commercial Solar
Solar panels for Irish businesses: costs, NDMG grants, and ROI.
Solar for Warehouses
Warehouse solar PV: sizing, NDMG grant, and ROI in Ireland.
Solar for Offices
Office solar PV: 9-5 load match, costs, NDMG grant, and ROI.
Commercial Solar Grants
SEAI NDMG up to €162,600, TAMS 3 for farms, ACA tax relief, and how to apply.
Sources
- SEAI, Non-Domestic Microgen Scheme (NDMG)
- SEAI, Accelerated Capital Allowance
- ESB Networks, Generator Connections (NC6 / NC7)
- Engineers Journal, Mannok rooftop solar (July 2026)
- ESB, Carey Glass rooftop array (June 2023)
- ThinkBusiness, Gyproc Kingscourt solar (April 2026)
- Checkout, Dawn Meats Grannagh solar (January 2025)
- ThinkBusiness, Tayto Snacks Ashbourne solar (March 2026)
- Global Cement, Irish Cement Platin Works solar (April 2026)
Last updated: November 2026
Fact-checked by John Rooney, Solar Energy Editor. Editorial policy
John Rooney is the editor of Solar Info and has been covering the Irish solar energy market since 2023. He fact-checks all content against official SEAI data and maintains relationships with SEAI-registered installers across Ireland.
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